From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Provisional Air Ministry General Specification for steel suitable for nitrogen hardening.
| Identifier | ExFiles\Box 146\1\ scan0118 | |
| Date | 1st March 1930 | |
| C O P Y. PROVISIONAL AIR MINISTRY GENERAL SPECIFICATION NUMBER D.T.D.87. for STEEL SUITABLE FOR NITROGEN HARDENING. -------------------------------- March 1930 Reprinted August 1932. Note. - This Specification is one of a series issued by the Air Ministry either to meet a limited requirement not covered by any existing British Standard Specification or to serve as a basis for inspection of material whose properties and uses are not sufficiently developed as to warrant submission to the British Standards Institution for standardisation. -------------------------------- The heat treatment temperatures specified have been selected as representing an average figure for general practice for the particular class of material, and are given in the specification as guides. Where variation from the specified figures is found to be necessary, the exact temperature must be stated in the test report. -------------------------------- Section I. General Requirements. The material shall comply with the requirements of the latest issue of B.S. Specification S11, excepting where modified herein. I. CHEMICAL COMPOSITION. - The steel shall contain: Carbon........ Not less than 0.35 or more than 0.45 per cent. Silicon....... Not more than 0.45 per cent. Manganese..... Not more than 0.65 per cent. Sulphur....... Not more than 0.05 per cent. Phosphorous... Not more than 0.05 per cent. Nickel........ Not more than 0.25 per cent. Chromium...... Not less than 1.40 or more than 1.80 per cent. Aluminium..... Not less than 0.90 or more than 1.30 per cent. Molybdenum.... Not less than 0.10 or more than 0.25 per cent. Vanadium and Tungsten may be present at the option of the steelmaker. | ||